Low pressure fuel burner



Jan 17, 1939. K, MCCONNELL 2,143,993

LOW PRESSURE FUEL BURNER Filed July 2'7, 1956 A TTORNEYS.

Patented Jan. 17, 1939 UNITED STATES PATENT OFFICE Richard K. McConnell,Oklahoma City, Okla., assignor to Phillips Petroleum Company, acorporation of Delaware Application July 27, 1936, Serial No. 92,886

1 Claim.

The present invention relates to fuel burners, and more particularly tolow pressure burners for gaseous fuels.

Present day fuel burners employing gaseous substances as the combustiblemedium, and known to applicant, require relatively high gas pressuresfor their satisfactory and efilcient operation. Pressures from 15 poundsper square inch and up are generally required.

In many instances, however, the available gas pressure is much lowerthan the minimum pres-. sure of 15 pounds per square inch, thusresulting in inefficient and unsatisfactory burner operation, and inmany instances, when extremely low pressures are encountered, theinefficiency is so pronounced that furnace temperatures or boiler steampressures cannot be maintained.

It is of course obvious that a result such as above described requiresthat the gas pressure be raised which in turn raises the cost of gastothe operator. I

In well drilling in particular, low gas pressures are frequentlyencountered thereby causing serious losses to the drilling contractorwho must have adequate steam pressure at all times to return a profit.Cessation of drilling operations even for a short time while awaitingadequate steam pressure means a substantial loss to the contractor andmay mean'a subsequentloss to the producer if the well is not completedin time.

It is therefore an object of the present invention to provide a burnerrequiring relatively low gas pressures for efiicient operation.

Another object of the present invention is to provide a gas burner inwhich a satisfactory mixture of gas and air may be obtained even at lowoperating pressures.

A still further object of the present invention is to provide a burnerof simple construction, economical and easy to operate and of low cost.

Other objects and advantages of applicant's invention willbe apparentfrom a consideration of the specification in conjunction with theaccompanying drawing forming a part thereof, in which Fig. 1 is anisometric view of the burner,

Fig. 2 is a sectional view, taken on the line 2.-2 of Fig. 1; looking inthe direction of the arrows.

Referring particularly to Fig. 1, 10 indicates a burner section whichmay be employed as a single unit or may be used in conjunction withother sections to form a burner block. An individual section, or aseries of such interconnected sections may be installed in the fireboxand the other faces the firebox interior.

and cemented in a wall thereof in such manner that one face is exposedto the furnace exterior The burners may be placed in an uprightposition, a horizontal position, or in any other position dictated bythe type. of furnace or boiler in which the burner is to be used, itbeing understood that the burner will operate in any position. A burnerbody or frame is indicated at II which is hollow to provide a fuelchamber M (Fig. 2), provided 1 with sides H and faces l2 and I3, whichis in communication with another burner section or with a source ofsupply, through the conduits l5, which in the present instance areindicated as nipples provided with screwthreads 16. -While the burnerbody H is shown as of box-like configuration, it is obvious that othershapes may be substituted. A series of oppositely disposed apertures Hin the faces l2 and I3, connected by tubular members It, form fuelmixing conduits 20 in which gas and air are properly intermixed prior tocombustion. Each of these conduits is provided with a cylindricalportion 2| extending for a portion of its length, and which terminatesin an abrupt shoulder 22 which in turn joins with a tapered portion 23terminating in the burner face l2. A fuel jet or port 24 in the form ofa bore extending through the wall of each of the tubular members l8 atan acute angle to the axis thereof, terminates in the shoulder 22 andserves to inject gas from the chamber l4 into the mixing conduit 20 insuch a manner and at such an angle that the direction of flow willintersect the axis of the mixing conduit at a point within the taperedportion 23 but adjacent the flame opening in the face 12, whereby athorough mixing of gas and air is obtained even though the gas pressureis of a low order.

It is to be understood that the burner may be cast or otherwise formed,and that the jets 24 may be drilled through the conduit walls aftercompletion of the body portion.

In operation a burner section or a series of interconnected burnersections are sealed into the firebox opening with cement so that theface 45 I2 faces the interior and the face IS, the exterior of thefirebox. It will now be evident that air for supporting combustion mustpass through the burner apertures l1 and the mixing conduits 20 underthe influence of the furnace draft. As 50 this air passes through theconduits 20, it is intermixed with the proper portion ofgas issuing fromthe jet 24. Thorough mixing is accomplished by conducting the air, atthe point of gas admission, through the tapered portion 23 of the 55 Insome instances, additional air may be supplied by cementing the burnerblock loosely in the firebox opening.

Applicant's burner" has proved its eflicacy on pressures as low as 0.5pound per square inch and excellent results are obtained on pressures offrom 1 to 3 pounds. 0n actual installations,

not only have burners embodying the present invention operatedsuccessfully on gas pressures within the range above stated, but morecomplete mixing as indicated by flue gas analyses and increased boilerratings over replaced high pressure burners indicate the desirability ofutilizing burner of this type operating at low pressure, in manyinstallations, even when high pressure gas is available. In actual testsit has been determined that applicants burner consumes about 18% lessfuel per B. H. P. than the burner previously used and the developed B.H. P. was increased 25% The foregoing specification and drawing forminga part thereof describe a preferred embodiment of my invention, but itis to be understood that applicant intends to limit his invention onlyby the scope of the subjoined claim.

Having thus described my invention, I claim:

In a low pressure gas burner for firing a boiler, a hollow body forminga gas chamber for the reception of gas from a source, a conduit definedby walls extending through said chamber from one side of said body tothe other, said conduit thus presenting an entrance at one side of saidbody and an exit at the other side of said body, said conduit having aportion of uniform cross section extending inwardly from said entranceto a point intermediate its length, said conduit being enlarged at thispoint to present a shoulder, said conduit walls tapering from saidshoulder to said exit, a bore in said walls connecting said gas chamberand said conduit, said bore opening in said conduit in a port located onsaid shoulder, the direction of said bore being such that a linetherethrough extended, intersects the axis of the tapered conduit-at apoint within the tapered portion but adjacent the exit.

RICHARD K. Mccomzm.

